Neurons & Signaling
Zoom all the way down to the cellular level and learn how neurons and supporting cells allow the nervous system to communicate.
Meet the neuron
Neurons are specialized cells that communicate information throughout the nervous system. Although neurons come in many different shapes, many have a cell body, dendrites, an axon, and structures involved in communication with other cells.
Anatomy of a neuron
This diagram shows the major structural components of a neuron and how they are arranged for communication.
Dendrites
Dendrites commonly receive information from other cells and conduct signals toward the neuron cell body.
Cell body
The cell body contains the nucleus and supports the neuron's essential metabolic activities.
Axon
The axon conducts electrical signals away from the cell body toward other cells or target tissues.
Axon terminals
Axon terminals form communication points where signals can be passed to another cell.
A neuron is built around communication.
Its different structures work together to receive information, conduct signals, and communicate with other cells.
How a signal travels
Electrical activity can travel along a neuron's membrane. At many chemical synapses, electrical activity leads to neurotransmitter release, allowing information to cross the space between cells.
Neurons and glial cells
Neurons are only one major cellular component of nervous tissue. Glial cells perform a variety of important supporting and regulatory functions.
Astrocytes
Astrocytes provide structural and metabolic support and help regulate the environment surrounding neurons.
Oligodendrocytes
Oligodendrocytes produce myelin around portions of axons in the central nervous system.
Microglia
Microglia participate in immune defense and tissue maintenance within the central nervous system.
More than support
Glial cells are active components of nervous tissue and contribute to its structure and function.
Why synapses matter
Synapses allow neurons to communicate with other neurons and target cells. Chemical synapses use neurotransmitters, while electrical synapses allow electrical current to pass directly between connected cells.
From the whole nervous system down to one cell.
You have moved from the overall organization of the nervous system to its major structures and finally down to the cells responsible for neural communication.
Ready to test your knowledge?
You've reached the end of the Nervous System course. Take the final assessment to see how well you understand the material you've just learned.
Take Final Assessment →